| Jarvis Jewellers (Gloucester) Limited | Wholesale & retail | 2018 |
| Jaslyn Embroidery & Print Ltd | Manufacturing | 2009 |
| Jasmin Cosmetics Ltd | Wholesale & retail | 2025 |
| Jason Ayers Ltd | Real estate | 2023 |
| Jatik Ltd | Information & communication | 2025 |
| Jatinderjit Limited | Wholesale & retail | 2020 |
| Jatsay Care Ltd | Health & social care | 2012 |
| Java (ML94) Limited | Financial services | 2022 |
| Javelin Property Ltd | Real estate | 2025 |
| JAX Electrical Services Ltd | Construction | 2019 |
| Jayne Hibbitt Smith Ltd | Information & communication | 2015 |
| Jays Timber Limited | Administrative & support | 1991 |
| Jaytech Systems Limited | Information & communication | 1998 |
| Jayz Jewels Ltd | Manufacturing | 2017 |
| Jazmins Collections Ltd | Wholesale & retail | 2025 |
| Jazoodle Limited | Information & communication | 2016 |
| JB & Sons Limited | Hospitality | 2020 |
| JB Brewery Ltd | Manufacturing | 2025 |
| JB Electrical Solutions Ltd | Construction | 2020 |
| JB Event Hire Ltd | Administrative & support | 2021 |
| JB Sporting Events Limited | Extraterritorial | 2019 |
| JB Three PVT Limited | Real estate | 2025 |
| JBA Energy Solutions Ltd | Professional & scientific | 2023 |
| JBS Clarke Investments Limited | Other services | 2022 |
| JBS Group Holdings Ltd | Financial services | 2023 |
| JBS Mechanical Ltd | Construction | 2015 |
| JBS Plumbing & Heating Division Ltd | Construction | 2023 |
| JCA Logistics Ltd | Transport & logistics | 2018 |
| Jclp Limited | Real estate | 2024 |
| JCW Property Ltd | Real estate | 2019 |
| JD Business Enhancement LLP | | 2019 |
| JD Construction (Glos) Ltd | Construction | 2013 |
| JD Plastering Limited | Construction | 2019 |
| JD Resus Limited | Health & social care | 2012 |
| JD Security Ltd | Administrative & support | 2025 |
| JDB Cleaning Services Ltd | Administrative & support | 2024 |
| JDC Electrical & Solar Installations Ltd | Construction | 2026 |
| JDE Electrical Ltd | Construction | 2020 |
| JDM UK Group Limited | Hospitality | 2023 |
| Jdrg Communications Limited | Professional & scientific | 2023 |
| JEB Accountancy Ltd | Professional & scientific | 2014 |
| Jed's Cleaning Services Limited | Administrative & support | 2022 |
| Jed's Properties Limited | Real estate | 2022 |
| Jedap Ltd | Real estate | 2026 |
| Jed’S Careservices Limited | Public administration | 2023 |
| Jefferies Social Work Ltd | Health & social care | 2019 |
| Jelf Developments Limited | Construction | 2016 |
| Jelly Bears Ltd | Health & social care | 2017 |
| JEM Drain Care Ltd | Administrative & support | 2022 |
| Jemjo Ltd | Transport & logistics | 2015 |
| Jemm Technical Project Services Ltd | Professional & scientific | 2025 |
| Jemma Travel Ltd | Administrative & support | 2024 |
| Jempason Properties Ltd | Real estate | 2020 |
| JEN Properties Limited | Real estate | 2022 |
| Jenkins Developments (Glos) Ltd | Construction | 2018 |
| Jennifer Sterry Limited | Other services | 2015 |
| Jennings Aldas (2019) Limited | Construction | 2019 |
| Jensen Accountancy Services Ltd | Professional & scientific | 2008 |
| Jeremiasz Properties Ltd | Real estate | 2025 |
| Jeremy Davies Property Management Ltd | Real estate | 2014 |
| Jerningham Management Company (NO.1) Limited | Households | 2013 |
| Jessica Louise Creative Limited | Information & communication | 2024 |
| JET Taxis Ltd | Transport & logistics | 2024 |
| JET2IT Drainage Solutions Ltd | Water & waste | 2023 |
| Jetify Ltd | Wholesale & retail | 2025 |
| Jetsettv Limited | Information & communication | 2024 |
| Jezco Limited | Real estate | 2016 |
| JF Holdco Limited | Financial services | 2023 |
| Jfc.Digital Ltd | Information & communication | 2024 |
| JFM Marketing Limited | Administrative & support | 2018 |
| Jforb Limited | Financial services | 2021 |
| JFP Finance Limited | Financial services | 2026 |
| JFP Investments Ltd | Real estate | 2021 |
| JG Swift Logistics Ltd | Transport & logistics | 2026 |
| JGB Engineering Ltd | Manufacturing | 1992 |
| Jgisby Ltd | Health & social care | 2014 |
| JGT Consultancy Ltd | Professional & scientific | 2023 |
| JGT Rail Services Ltd | Construction | 2022 |
| JH Restaurants Ltd | Hospitality | 2019 |
| JH Tree Services Ltd | Agriculture & fishing | 2021 |
| JH14 Promotions Ltd | Arts & recreation | 2024 |
| JHL Developments Limited | Real estate | 2026 |
| JHS Electrical (Gloucestershire) Limited | Construction | 2025 |
| Jigsaw Recovery Group Limited | Administrative & support | 2026 |
| Jimmeways Consult Limited | Professional & scientific | 2022 |
| Jinxing Takeaway Ltd | Hospitality | 2019 |
| JJ Carpentry & Property Maintenance Ltd | Construction | 2024 |
| JJ Electrical Connections Ltd | Construction | 2016 |
| JJ Enterprises Gloucester UK Limited | Administrative & support | 2025 |
| JJ Roofing Specialists Ltd | Construction | 2024 |
| JJB Media Ltd | Wholesale & retail | 2011 |
| Jjbakeruk Limited | Hospitality | 2018 |
| JJE Creative Ltd | Construction | 2019 |
| JJH Arboriculture Limited | Professional & scientific | 2026 |
| JJH Property Development Ltd | Real estate | 2026 |
| JJL Carpentry Contractors Limited | Manufacturing | 2020 |
| JJL Electrical Ltd | Other services | 2021 |
| JJL Property Management Limited | Real estate | 2021 |
| Jjohnsonproperties Limited | Real estate | 2025 |
| JJR Global Ltd | Wholesale & retail | 2021 |